Amid the grief so many feel at Robin's tragic loss, so sudden, so unexpected, we take comfort that today so many have come together from so many parts of the world to celebrate Robin's life and that we have gathered here in the heart of Edinburgh:

- within half a mile of the old Royal High School and of Edinburgh University where Robin first developed the commitment to justice that shaped his life's work;

- across the road from Edinburgh council chambers where Robin first gave public expression to that commitment;

- only a few yards from his first constituency office, where he began 31 years of tireless work as an MP - translating that principled commitment to social justice into practical social change;

and we honour Robin today fittingly in this cathedral where Scottish history teaches us - what Robin always believed - that power must be accountable to the people. This cathedral where famously one enraged citizen lacking Robin's eloquence and powers of persuasion - spoke truth to power by hurling her seat at the preacher, with whom she disagreed. And there will be no one in this congregation who will have any doubt on whose side Robin would have been.

And today here - as we celebrate Robin's life and legacy of public service and mourn our loss - our thoughts and prayers are with those closest to him for whom the grief today is greatest. His wife Gaynor who shared his ideals, lovingly supported him in his work and was at his side as he passed away. Peter and Christopher, his sons, to whom he was so devoted and of whom he was so justifiably proud. Their mother Margaret and the wider family all of whose sorrows we share today.

And let us acknowledge Robin's passing leaves a gap that can never properly be filled. In the six days since he was taken from us, Tony Blair, John Prescott, all who have spoken or written from all political persuasions and none - have rightly praised Robin's singular achievements as MP, Foreign secretary, leader of the House of Commons in Tony Blair's government - and his unsurpassed mastery of parliament.

Today we salute him as the most accomplished parliamentarian of our generation, who brought democracy closer to the people. And those of us privileged to serve with him know that the extraordinary abilities that the public saw Robin put to masterful and crushing effect in the Scott Inquiry - the forensic skills, the irrefutable logic, the devastating wit, the telling phrase that made people see things in a way they had not seen them before - these were the qualities he manifested consistently and brilliantly in stunning performance after stunning performance throughout more than three decades: for all of us who watched, a thirty year long master class in effective eloquence that gave people new faith in democracy itself.

Indeed at times Robin, at his most brilliant, could, to rephrase Shelley, make even legislators look like the unacknowledged poets of the world. A mastery that could not only bring people to their feet but could - and did - bring opponents to their knees and sometimes even to their senses.

And what grieves us so much today is not only the personal loss we all feel so deeply but the greater loss: that Robin has been taken from us at the height of his powers, with causes still to be advanced, public service still to be rendered, a contribution now lost that will diminish us all. The rhetorical skills, the incisive humour, that supremely crafted eloquence that sometimes like a flash of lighting could reveal for us new landscapes, are necessary to understanding Robin's greatness, but they are not sufficient to explain just how great and enduring is his contribution.

I am here today to affirm that to Robin we all owe so much more.

He was a great orator whose mission was far more than that: his mission and his achievement was not just to make great speeches but to advance great causes - and he did. His speeches soared, but so too did his vision.

For him, words had to have a purpose, eloquence had to be driven by conviction, biting wit, especially scorn, had to have a point and not simply be the acceptable face of malice. His skills, his gifts had to serve higher goals.

And those who characterise him simply as a supreme debater - they forget that the dominant force shaping his life was what he was debating for - a lifelong, deeply-held passionate commitment to social, political and economic justice.

And this is how I believe we best remember Robin - not just for what he said and how well he said it, but what he stood for.

The greatest parliamentarian of our time put all his talents and his life at the service of the greatest causes of our time - to right wrongs, to equalise life chances, to advance opportunity. Whenever there was injustice, he sought to right it. Wherever there was poverty he fought a war against it.

He was in politics not to be something but to do something, not to get what he could but to give all that he could, there not to seek power over principle but to seek power for principle.

Whenever or wherever there was poverty, injustice or unfairness, this is where Robin's voice became a mighty force locally, nationally and internationally.

And even amidst times of turmoil and turbulence, amid the inevitable ups and downs, the tensions and divisions of politics, there was a constancy in his deeply held beliefs as true when he began his public service with a plan to clear the last slum housing from Edinburgh right up to the last when his Guardian articles burned as red as his hair, with the same passion and the same purpose.

His life a standing reproach to those who say that power corrupts people's beliefs.

And the last time Robin marched - and he marched often over these years - he walked on July 2 only a few yards from here along the bridges down the Mound. Quietly and unannounced - he, the former foreign secretary with Gaynor at his side - part of a crowd of tens of thousands walking with people to Make Poverty History.

And why?

Because he was the grandson of a miner, whose life of struggle had taught the Cooks not selfishness but the importance of solidarity. He was the only son of a socialist headmaster and wonderful mother he adored who both believed that true equality of opportunity would lift people up not level them down.

Educated in literature and history, but having started a thesis on Victorian novels and their impact on society, he concluded quickly that there were for him more direct means to achieve an impact on society. He mused, even with an outstanding doctorate he might have changed a footnote in a literature textbook, but Robin wanted to change the world.

And we think of Robin alongside John Smith and Donald Dewar in that generation that growing up in Scotland in the postwar welfare state went out to defend it as a great civilising advance and the NHS defended as a miraculous deliverance from evil.

And we can perhaps see more clearly from his background now that this complex character - driven, hard to get to know, yet at a personal level often so considerate - was shaped in a world where it was assumed that nothing could be taken for granted, everything had to be fought for. And if we had talents we had a special duty to work ceaselessly and use them for others.

His first big job, to transform the Workers Educational Association from its image rooted in the 1930s - all its members, Robin said, seemed to have known Keir Hardie personally - and typically, like his friend to be, Neil Kinnock in Wales, he planned courses about the future not the past for what Neil eloquently called the liberation of untapped potential. And when I started as a part time WEA tutor Robin was very kind indeed. He told me not to take it personally - and the WEA kept me on - after only one member turned up for my first class, and no one turned up for my second.

And then the energy, thrill and mischief of his first parliamentary campaign - where Robin himself was almost arrested. A few weeks ago Robin and I laughed together at the irony of Robin, the young candidate, portraying his Tory opponent as out of touch and unelectable because this opponent spent much of his time riding a horse: Robin's election leaflets picturing an MP on horseback in full hunting gear - with the caption "Does this man really represent you?" - a leaflet of a kind, we joked, he was unlikely to want distributed in Livingston.

Parliamentary candidate at just 24; at 25 a councillor - one of a remarkable group of men and women, many here today - at 26 Chairman of Edinburgh Housing Committee and by his 28th birthday one of Britain's youngest MPs. And then for 31 years Robin did everything for his constituents an MP could do: the unpublicised thousands of hours he spent. Even when burdened down by Kosovo and global duties he visited schools, fought for St John's hospital, he marched to save jobs. When foreign secretary he insisted that the first entries in his ever crowded diary had to be his local surgeries and the local galas.

And he came to love Livingston - not least the local factory that made the biscuits which happened to grace the Foreign Office. Typically, Robin, on a well publicised visit to the factory, briefed the press his favourite above all among the biscuits. He spoke in the way he often did, with one eyebrow raised, that mischievous twinkle in his eyes that all of us recall and have on occasion been at its receiving end: "I like the ginger cookies best", and then adding with that theatrical flourish we also remember: "I can testify from personal experience how good they are".

And the fact that in the election only three months ago Robin recorded his highest ever majority is testament not just to Jim Devine and his many friends in Livingston Labour party but to a large personal vote - as I found addressing Robin's 25th anniversary celebration as an MP - that the people understood that he was there for them, they trusted him and knew he was on their side. For them there was no more insistent voice for justice.

And this was the essence of Robin: whether in Livingston or London, with constituents or in the Commons, in corridors of power in Europe or across the world, a voice for the voiceless, a champion for those who had no power, a tribune for those whose hopes he believed had to be heard.

And this is how we will remember Robin. As a foreign secretary of the first rank. A European. An internationalist. His ethical mission, the advancement of rights for people denied them, his first act was to restore the voice of trade unionism to GCHQ; who banned land mines; who, with Tony and now Jack Straw worked tirelessly for Middle East peace; who strove to banish ethnic cleansing from the Balkans and saved the lives and limbs of many who will never know his name; with Joschka Fischer, here today, he advanced European unity; who played the key role in the removal of Milosevic; who was unafraid to intervene to send troops not only to Kosovo but to Sierra Leone to save that tortured land.

His noble vision: a world where the just became powerful and the powerful became just.

Never, of course, with Robin agreement simply for agreement's sake, always rigorous - sometimes exasperatingly so, never a yes man, and not infrequently quite the opposite - but even when we disagreed I respected he argued from principle.

The position of leader of the Commons was one which - to put it mildly - he had neither sought nor contemplated, and certainly had not volunteered for.

But for Robin public disengagement from politics was a real threat to democracy and his vision of a good society. To make parliament less of a political museum and more of what he saw it should be - our country's national forum for debate - he opened up the Commons: its hours, proceedings, facilities and accessibility.

Joking that it was no longer good enough to run it as if for the convenience of a coterie of London barristers - and only after a wicked pause adding quickly - of the 18th century of course, by sheer force of personality and leadership Robin inaugurated more modernisation in just two short years than any of his predecessors had achieved in two hundred years.

So when Robin resigned over Iraq no one ever doubted that his decision was founded on principle and the manner of his departure became the true measure of the man.

For we can now understand why it was that a man true to his conscience could in circumstances of such controversy leave government in a way that not only manifested an absence of rancour but won applause not just from those who agreed with him but those who disagreed with him.

I believe that notwithstanding the real and profound disagreement with that government policy, Robin never wavered in his loyalty to the Labour party which was his political home. Back in the long years of opposition, Robin often quoted Aneurin Bevan as his guide: "It's the Labour party or nothing. I know all its faults but it is the party we have taught millions of working people to look to and to regard as their own". And no one fought harder than Robin to win the last election.

And when Robin's radicalism and sheer restless intelligence led him to think not just deeply but often controversially, sometimes beyond party strictures on great issues - on nuclear power, the environment, constitutional and electoral reform - even when he differed with the party line - or over the pluralism he rightly championed, no one ever doubted his Labour credentials and everyone recognised the distinctive contribution he made.

And that is why Robin will always stand high as an inspiration alongside John Smith and Donald Dewar in that great generation of Labour Scots: their background the professions, their inspiration a strong social conscience, their ethic public service; their abiding goal, justice and democratic socialism.

"One must wait until the evening," said Sophocles, "to see how splendid the day has been". Perhaps sadly it is only over the last week since Robin's time has ended that we have come to recognise the breadth and depth of an astonishing life of service; the loss we have all suffered; and the memorable moments - the vivifying conversation, Robin's tireless idealism, the wit, humour and irony, the individual kindnesses - that we will never now see again.

And as tributes have flowed, I believe it could be said of all of us that we did not value Robin enough in life.

Robin knew victory and he knew defeat. He knew triumph and he knew despair. Robin climbed many mountains and he scaled great heights. When last Saturday he died suddenly in his prime he was still climbing to the mountain top.

In the words spoken long ago of another great life cut all too short: "He had not yet passed on life's highway the stone that marks the highest point".

And let we who are gathered here say to Gaynor, to Peter, to Chris, who we know will miss him most, even amidst the pain take pride that his bright shining memory will outlast the darkness of this past week and will inspire us and others further and higher on the road ahead.

In the poem Praise of a Man by Norman McCaig we find words that speak to us today:

The beneficent lights dim but don't vanish. The razory edges dull, but still cut. He's gone: but you can see his tracks still, in the snow of the world

So let us draw strength from Robin's achievements that light the way ahead.

Let us affirm his work will go on. That those who heard him as a voice for justice will have their voices heard. That justice will be championed wherever there is injustice and in every corner of our country and our world.

And guiding us on that onward journey, now and in the days ahead, Robin's values, Robin's service, Robin's passion for justice.